Posted
by
CmdrTacoon Wednesday November 05, 2008 @10:12AM
from the isn't-that-exciting dept.

bmcage writes "The ESA unveiled the Intermediate eXperimental Vehicle, a real re-entry vehicle. Although it will not be reused, it has a better geometry than NASA's Orion or the Russian Soyuz, giving better lift, and control. This is not done by the addition of useless wings, but by using two brakes. Finally a departure from the Apollo design that is actually better?"

They're planning on launching this in 2012, and it's just a test. What with delays, bureaucracy and imminent lack of funding due to the world economy, you can't expect Europe to get actual people into space until at best 2018, at which point American private companies, Russia, and China will be headed for the moon, if not already there. The Orion program seems much the same to me.

You're somehow assuming that bureaucracy and lack of imminent funding won't affect Rusia, China and American private companies...As far as I understood it Russia's space program is severely under-funded and China's most optimist schedule is man in space in 2012 so maybe it's not that bad.

China has launched men into space since 2003 (again in 2005 and September this year). ESA's plans for it's own manned space launches are little more than concepts at this time and would require much more funding from the European governments unless they want to cut all the robotic missions. ESA does have it's own astronauts who ride on American or Russian launchers, and ESA built and owns parts of the ISS.

IXV that this article is about is a small testing platform, not a manned spacecraft.

I must disagree. The ESA programme is designed to improve spaceflight in small steps. They try to be very cost effective. And this path has brought them the biggest market share in space cargo delivery (in form of Ariane Space).

ESA has also a Mars programme called Aurora, which includes the delivery and return of humans. But before going there, technologies have to developed which can transport objects into space and safely return them. And because the Europeans do not think they are participators in a race

SpaceShipOne and SpaceShipTwo were purely sub-orbital; they were glorified rocket planes that didn't carry anywhere near the fuel necessary to reach orbital velocity. SpaceShipThree, on the other hand, will reach orbit, but it will almost certainly be a multi-stage craft.

And while discarding empty fuel tanks may be wasteful, it would be far more wasteful to expend the enormous amount of fuel required to carry the entire craft to orbit.

Until we find a better means of propulsion than rocket fuel, multi-stage craft are the most resource-efficient means of attaining orbit.

Pretty much. And frankly wings are not that heavy. The shuttle didn't just have a very large crossrange requirement but also a huge bring back capability.The Shuttle is capable of bringing the Hubble back to be worked on if needed. In fact the plan was for the Shuttle to bring back the Hubble so it could sit in a museum when it's life is over.It is a capability that has never really been used except for the SpaceLab flights.Frankly the Shuttle was an attempt to jump from the Wright Flyer to a 707. We really needed to build a Ford Trimotor and a DC-3 first.

[Shuttle cargo return] is a capability that has never really been used except for the SpaceLab flights.

There was also the Long Delay Exposure Facility [wikipedia.org]. They've also returned the work platforms, fixtures, and special tools used for Hubble repair. They've also returned the the Spacehab cargo containers (pressurized and unpressurized) used for delivering cargo to the ISS. They've also returned the MPLM [wikipedia.org]s used for cargo delivery to the ISS - the only system capable of delivering full sized equipment racks. The

Not exactly. I probably should have made the statment clearer. The shuttle has an excessive bring back capability that is hardly ever needed.Every space craft has some bring back capability. The shuttle's is HUGE and as I said hardly ever used to it's maximum.The shuttle could have been lighter if the it had a reduced bring back capability.Of course you do loose another capability and that is a safe abort that saves the vehicle.If the shuttle couldn't land with a full load then if an abort happened the crew

"If you reduce bring back capacity you also reduce lift capacity, the two are directly related."No they are not. The bring back is limited by the lift of the wings and the strength of the landing gear.Lift is limited by thrust.A prime example is many airliners can take off with a lot more weight than they can land with.And man you are nit picking.I was speaking of an abort to Kennedy. Which would be very clear since a mentioned that you would still be overweight to land. In an ATO you could dump your cargo

"If you reduce bring back capacity you also reduce lift capacity, the two are directly related."No they are not. The bring back is limited by the lift of the wings and the strength of the landing gear.

Ah yes, the strength of the rest of the structure has no bearing.

Lift is limited by thrust. A prime example is many airliners can take off with a lot more weight than they can land with.

"Rockets aren't airliners. Lift is equivalent to thrust, lift capacity is constrained by numerous factors - of which thrust is only one."None of which have a lot to do with an aero dynamic bring back.The shuttle isn't just a rocket. It is a rocket and a glider combined.The shuttle's bring back is limited by the strength of the landing gear and the structure that supports it. Like the wing spars.It is also limited by the wing loading since that has an impact on the landing speed and landing stresses.So no in

Wings were added to the shuttle to respond to the the USAF's crossrange requirements & some of the early shuttle plans looked a lot like this.

By the time the USAF came aboard, the lifting body shuttle had been long abandoned (and had only briefly been considered in the first place) and wings to provide crossrange were already a key feature of the design. What meeting the USAF requirements entailed was to modify the planform, more of a major adjustment than a radical redesign.bmcage also needs

Mostly it is a testbed of the design and aeronautical controls. Looking at the movie's many exploded and shaded CAD views (nice touch, guys), it appears to have no cargo space whatsoever. It doesn't look to me like that's what they have in mind - they just want to show that the flight fundamentals of the design are sound. They can work on building a larger one for cargo and/or humans if they manage this first significant milestone.

There also doesn't appear to be any redundancy, which has long been a design contention in the US and Russian schools of thoughts. I don't know where the ESA is, philosophically, on this issue. But, the absense of thrusters in the nose leaves few options if the brakes fail or are damaged.

There also doesn't appear to be any redundancy, which has long been a design contention in the US and Russian schools of thoughts. I don't know where the ESA is, philosophically, on this issue.

This is easy: ESA has designed and is building and flying the most redundant and fault-tolerant unmanned spacecraft ever seen on this small planet: the ATV [esa.int].

In an extreme case these things are able of successfully completing their missions with half of the solar panels and fuel tanks and 2/3 of everything else (including computers, antennas, sensors, fuel lines, thrusters, actuators, electrical lines, etc...) completely damaged. Of course this is theoretical, since they would abort the mission in these circumstances, to keep the ISS safe. But still as demonstrated by the first ATV, the Jules Verne, they can successfully complete a mission with any single failure in any subsystem except the main fuel tanks.

But, the absense of thrusters in the nose leaves few options if the brakes fail or are damaged.

Hmm... I'm not a rocket scientist, but you seem to know even less than me about this. Anyway this is only a technology demonstrator and one-time test.

There also doesn't appear to be any redundancy, which has long been a design contention in the US and Russian schools of thoughts. I don't know where the ESA is, philosophically, on this issue. But, the absense of thrusters in the nose leaves few options if the brakes fail or are damaged.

ESA's philosophy is: don't add redundancy for pretty much the only thing your going to test.

Good grief, who writes this stuff anymore? I'm sure ESA's ideas are interesting and innovative, but making this out to be the savior of the manned space program is a bit facetious to say the least.

Is it not essentially a lifting body (in spite of some new ideas)? NASA pioneered this concept, which was intended to be applied to reentry vehicles at some point. The concept was most recently expressed in the X38B crew return v

Since when have wings become useless? Also looks to me like it is based very much on the Apollo program in terms of technology. Vertical lift multistage chemical rocket. Small capsule on top etc...

The real innovation in this space is coming from private companies like Burt Rutan's Scaled Composites. By doing things like using useless wings to get up to altitude before launch thus requiring less propellant. And using useless reconfigurable wings to act as air brakes etc..

By doing things like using useless wings to get up to altitude before launch thus requiring less propellant.

No, that doesn't work. The cheapest part of a spacecraft is its propellants, second cheapest is the propellant tanks, third cheapest is to buy or design a bigger engine at the start of the design process (kind of difficult later on in the development cycle). The most expensive part of a spacecraft is systems integration, and adding wings and horizontal flight is hard to integrate. The aerodynamics of ultra high speed wings is a huge pain, and simply isn't needed, so why bother.

You are probably not aware of the 666 rule... Not to keep you in suspense, mach 6 at 60,000 feet (thats 20 kilometers in the civilized world) is a whopping 6% of total orbital energy. An impossible speed at an impossible altitude provides practically no advantage over a simpler ballistic design with tanks that are about 1/20th bigger. Most people have the peculiar idea that a civilian airliner at cruise is "almost in orbit" and the slightest push is all that is needed for a 747 to reach the ISS, and that couldn't be further from the truth.

Making an airplane that flies at mach 6 and 60Kft is no laughing matter, and then making it also a spacecraft is simply unrealistic. On the other hand making the fuel tanks a bit larger is no big deal.

There are three advantages to air launch that apply in almost no situations. One is the obvious lack of ground support, don't need to license a "spaceport" just another airport, however the EPA, FAA, USAF, NORAD, BATF, etc are going to harass you just the same anyway so this is again another way to get a small advantage at a huge cost. I guess Rutan and friends thought it was worth it, but thats a regulation and political decision not a technological decision. The other advantage is for military purposes you can assume a large fleet of aircraft could simultaneously launch an even larger number of rocket vehicles from anywhere an airplane can fly, possibly at great surprise to the enemy, this is the nuclear tipped cruise missile idea applied to a suborbital ballistic trajectory, which isn't such a bad idea but never got much traction, at least in the USA. Maybe Rutan daydreamed of selling hundreds of his vehicles to the USAF for recon purposes or something. There is a third reason to airlaunch, if you're basically making a circus carnival ride as opposed to a real vehicle, then air launch makes the roller coaster ride even more spectacular.

There are three advantages to air launch that apply in almost no situations

Err I forgot there is a fourth theoretical advantage which relates to failure modes. 99.999% of serious launch failures will result in a giant fireball, an aluminum lawn dart, or a square mile debris field, but for that tiny fraction of survivable disasters, the more complicated air launch system can always glide home at any stage of the flight. Vertical launch systems almost always have a region at low enough altitude where a failure can't be survived. However, it's hard to find a failure mode that is b

You should also add that air launch is inherently reusable, that its cost is dramatically lower, that the carrier vehicle does not degrade in operation and could be ready for the next launch immediately, that in the event of post-detach launch failure the carrier provides observer and pursuit capability without extra air deployments, and possibly most important, that most of the dense atmospheric stresses are bypassed so everything can be lighter.

None of these things are proven, and most of them depend on the details of the system chosen.

Air launch does have some significant advantages, though; most notably in the way of range safety: you don't light the rocket until you're in a clear space, well away from ground assets.

SpaceShipOne has been proven to work, but thats not a very good argument, since it was never intended to scale up to an orbital vehicle. The difference in energy required for that flight and an orbital flight is about 1:10, meaning that an air-launch reduces the energy cost by ~50% for a sub-orbital flight rather than ~5% for an orbital flight, making it much more worthwhile. This is why Rutan did it this way, but I'm pretty sure if he's considering SS3 much right now, he'll go with a very different archi

Well my point still stands this ESA module has a lot in common with the Apollo program.

And that the really innovative thinking is in the private sector right now. I doubt though can not prove that ballistic rocket with capsules or reentry vehicles or what have you will NOT be what lowers the cost of access to space and will NOT be safe anytime soon. It will take someone like Rutan or Zubrin to challenge traditional thinking with a new idea.

The first stage of an air launch vehicle does not need to carry it's own oxidizer as it can use air breathing engines, and some of the weight (lift) is carried by aerodynamics (wings) instead of pure rocket power. I don't think there are any air breathing engines (jet) with enough thrust to work in a pure vertical liftoff first stage, but if that were possible then some of the weight (oxidizer) could be saved in a re-usable first stage.

I think the ESA is on the right track. A shuttle like this should be small and cheap with no real facilities except for transport. All of the scientific and life-support facilities should be on the space station. Shuttles should just transport cargo and/or crew.

Well, some life-support is neccessary - not only does the shuttle need a bit of time to reach the space station, there might also be a problem that keeps the shuttle from immediately re-entering/reaching the station.

Think of the Space Shuttle Columbia: It would have been possible (and was recommended by certain people) to check the hull of the shuttle before entering the athmosphere and, in case of a fault (which we now know existed) attempt a rough patch-up or wait for another shuttle to rescue the astro

By "life support", I mean bunks, full-size toilets, the whole 9 yards. I think that if there's a problem with the new shuttle, just docking with the space station (or doing a spacewalk to the station) is their best bet. But, you really can't plan for everything.

1) So does it use the same sort of heat resistant but very fragile tiles that the space shuttle uses? Is that why it has a shroud covering it during launch (adding weight and complexity)?

2) Will this be able to work at very high re-entry speeds not just from earth orbit but from lunar/mars return missions? The video (at the very end) seems to imply this. (Couldn't tell from the wind tunnel footage; shows only shock waves at Mach 1.4. And no CFD simulations!).

Since it's not reusable, the fragile heat resistant tiles are not a problem. The shroud is for aerodynamic control during launch, you can see in the video that the vehicle is a lifting body; have it sit exposed on top of the rocket would give you huge off-axis forces due to drag/lift.
Single stage to orbit doesn't make sense from a fuel economy point, you need a lot of big engine at the beginning, why accelerate all that mass into orbit? Ditto on reentry, you have to bleed off all that additional energy you put in, requiring lots more of those fragile heat shield tiles.

SSTO only really becomes viable when you're talking about reusable vehicles operating at high flight rates, like better than once a week.

Space access will be routine when your launch vehicle can be prepped in a winter snowstorm by hung-over ground crews tired from fighting with their spouses the night before, and when they can take the abuse dished out by swarms of small-children passengers. The current clean-room-and-army-of-men-in-bunny-suits method just isn't economical. Unfortunately, it will take a m

We aren't talking about making a runway approach here, so who needs all this control (besides some frustrated pilot astronaut)? No control needed to hit the Pacific or even Central Asia; just timing.

I am also concerned about the total reliance on one big honker parachute, and wonder what the vehicle's speed will be (slowed by pure air drag alone?) when that main has to deploy. I'd feel a LOT better with a wee drag chute out the back (in case of control and/or parachute failure), and at least an escape hat

Complicated? I don't see how it's much more complicated than a parachute with a winch on a couple of the lines. Prone to failure? Practically all modern sport parachuting is done with parafoils. If they were more prone to failure than a standard dome chute, they wouldn't be used.

I think you answered your own question with not "much more complicated". This still implies that it is more complicated and you have to weigh the added risks with the added benefits and the design goal.

No, I haven't. A parafoil is only slightly more complicated than a parachute and gives you the tremendous benefits of controlled descent, and directional control. With a parafoil you can land the capsule on a helicopter pad on a rooftop, or directly on the deck of an aircraft carrier, or right in front of the hanger at the spaceport. With a parachute, you have no control whatsoever. You land wherever the wind takes you, and you have little control over how hard you land. If you open a little late, you

You need the control to make sure your "lander" doesn't roll. You only have one side of the vehicle protected via tiles, if you expose the other side you get fried astronaut with your fire work.
In regards to the chute, weight is everything at the orbiter stage, and landing gear adds a lot of weight. And if the main chute fails, I doubt you could manually exit the vehicle in a supersonic slip stream without ejection seats (which again are way to heavy).

You're right. What were they thinking! Those ESA engineers should come to Slashdot for their advice. We clearly have a better understanding of things than they do.

Seriously, though, would you want to re-enter earth with your heat shield above you? Or perhaps you'd rather add lots of weight by covering the whole thing in heat shielding? I'm sure they included a back-up chute.

"it has a better geometry than NASA's Orion or the Russian Soyuz" - is that because the Europeans use the Riemannian geometry instead of the Euclidean or is it merely thanks to a more consistent use of the metric system?

I think the idea of being able to exit an aircraft before it incinerates, or craters, is a good idea. But I think that the Engineers have missed a major flaw in Land-To-Space design. Burt Rutan's [typepad.com] solution allows for a more simple, graceful recovery of malfunctioning LTS Assemblies. Half the cost of an LTS project is the cost of Insurance for a second chance. By lifting parts of the project, and applying Final, and Trim Assembly in a stable earth orbit, one can reduce the overall project cost, and handle

Google the old NASA Dyna-Soar research vehicles of the 60's. This is nothing more than a lifting body.
Computer controlled, but still nothing more than a lifting body, add wings and you would have a mini space shuttle.